New Vanadium(V) Complexes with Salicylaldehyde Semicarbazone Derivatives: Synthesis, Characterization and In Vitro Insulin Mimetic Activity. Crystal Structure of [VVO2(salicylaldehyde semicarbazone)]

P. NOBLÍA; D. GAMBINO; L. OTERO; E. J. BARAN; P. DRAPER; H. CERECETTO; M. GONZÁLEZ; O. E. PIRO; E. E. CASTELLANO; T. INOHARA; Y. ADACHI; H. SAKURAI

EUROPEAN JOURNAL OF INORGANIC CHEMISTRY

Elsevier

Año: 2004 vol. 2004 p. 322 - 328

1434-1948

The new dioxo(semicarbazone)vanadium(V) complexes cis-VO2L, where L = salicylaldehyde semicarbazone (L1), salicylaldehyde 4-n-butylsemicarbazone (L2), or salicylaldehyde 4-(2-naphthyl)semicarbazone (L3), have been synthesized, characterized by 1H and 13C NMR and FTIR spectroscopy and tested for bioactivity as potential insulin-mimetic agents. All dioxovanadium(V) complexes exhibited essentially no in vitro insulin-mimetic activity, but the VO2L2 complex developed activity in the presence of ascorbic acid, similar to that of vanadyl sulfate. The molecular structure of the novel complex VO2L1 has been solved by X-ray diffraction methods. It crystallizes in the tetragonal space group P42/n with a = 12.7674(7), c = 11.5308(5) A, and Z = 8. The vanadium atom is in a distorted square-pyramidal coordination, with L1 acting as a tridentate ligand through its azomethyne nitrogen atom, carbonyl oxygen atom and deprotonated phenol oxygen atom. The coordination sphere is completed by two oxo ligands at cis positions.